In its zeal to reclaim an eroding fan base with its highly touted "back to basics" approach to stock-car racing, NASCAR overlooked one very basic thing: a racetrack that didn't erode during its marquee event.

The season-opening Daytona 500 was halted twice Sunday, for a total of 2 hours, 23 minutes, so track workers could patch potholes in the surface of Daytona International Speedway - a calamity that nearly overshadowed Jamie McMurray's improbable victory in a wild scramble on the final lap more than six hours after the race began.

McMurray, who lost his job at the end of last season, spun his Chevrolet in smoke-spewing circles of glee on the frontstretch grass after taking the checkered flag, then hopped out to grab the flag as a memento and dropped to his knees, buried his helmeted head in the grass and pounded the ground.

"It's unreal," McMurray said, breaking down in tears in Victory Lane after seeing his father and his wife waiting to congratulate him. "It's a dream."

Dale Earnhardt Jr. staged a thrilling show of his own, rallying from 10th to second over the final 10 laps of mayhem. Greg Biffle came home third.

"When I saw the 88 (Earnhardt Jr.) behind me, I thought, 'Oh no!' " McMurray said. "Earnhardts - they win all the time at Daytona!"

The fiasco of the fissures that erupted between the speedway's first and second turns, and the failure to fix them in a timely manner, amounted to a huge black eye on NASCAR's biggest occasion - equivalent to the NFL halting the Super Bowl in the fourth quarter because a goalpost collapsed and taking two hours to right it.

The action resumed at 6:31 p.m. EST, with NASCAR ordering the first stint to be run under the yellow caution flag, at 70 mph, as a precaution.

All but Scott Speed ducked into the pits for tires and gas, which gave Speed the lead.

NASCAR dropped the green flag on Lap 168, signaling a return to full-speed racing for the 33-lap sprint to the finish.

In the frenzy that ensued, four-time NASCAR champion Jimmie Johnson blew a tire and finished 35th.

A three-car pileup took place on the backstretch with six laps to go. Among those involved was 2008 Daytona 500 winner Ryan Newman.

Shortly after Bowyer brought the field to green, leading with two laps to go, another wreck happened.

Biffle had wrested the lead by then, but under NASCAR's new rule guaranteeing three attempts at a green-flag finish (rather than ending the race under a caution), NASCAR lined up the cars again.

Harvick darted low and got around Biffle, whose car was nearly turned sideways in the process.

Though broadcasters pointed to the more than 50 lead changes and furious side-by-side racing, the 52nd Daytona 500 fell far short of the fan-pleasing show NASCAR officials had hoped to stage.

With TV ratings steadily declining in recent years, NASCAR made significant changes to its rulebook on the eve of the Daytona 500 expressly to win fans back.

Among them: They gave the cars more horsepower and, in turn, more speed, to put the premium on handling and driver skill; they also rescinded a ban on the risky practice of bump-drafting, in which a driver intentionally rams the car in front to create an aerodynamic boost through traffic.

The upshot, NASCAR promised, would be a return to the sort of stock-car racing that fans fell in love with a generation ago, featuring plenty of fender-rubbing and paint-swapping.

Nostalgia was in the air from the start.

Seven-time NASCAR champion Richard Petty, 72, drove the pace car that led the 43-car field to the green flag.

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